Gramps will have to lower his expectations by a cubic ton(e).
I said it a thousand times (most of those times I was surely saying it in my head taling to myself...). If you feel your modeller sounds shitty answer those 2 1/2 questions:
a) Have you
ever had your amp miced?
If yes:
b) Have you
actually listened to how this amp sounded coming from the PA speakers or how it sounded on a recording?
Bonus:
c) Did you mic it yourself (as in: Did you physically pick the position (height, distance, angle) the mic has to the cab?)
There's
absolutely NO SHAME in answering all of those questions with NO, but then be open to learn something new. There's a world beyond having a real amp and a real cab and the best thing: They can all coexist. Play what makes fun.
I feel like a
BIG percentage of people buying any modeller is like "This doesn't sound
AT ALL like my Plexi, AC30 or Twin. Here, I can A/B them. The amp
here in my room sounds waaaay more lively and real!"
Every modeller company should put a leaflet inside the box reading "This is not your amp in the room. This is the simulation of a virtual pre amp going through virtual effects being powered by a virtual power amp and then being fed into a virtual cab/speaker, that most likely is just a specific EQ curve of a cab. No, it won't sound like the Plexi in your garage, that deafens you since 1982."